In the term estrogen, the combining form estr/o means:

[Answer to ques. #1]  D
Explanation: A) The prefix eu- means good.
B) The prefix exo- means away from.
C) The combining form thyr/o means shield or thyroid.
D) Correct. The combining form estr/o means female.

[Answer to ques. #2]  melena

[Answer to ques. #3]  D
Explanation: A) Cushing disease is caused by hypersecretion of adrenal hormones.
B) Graves disease results from hypersecretion of the thyroid hormones.
C) Diabetes mellitus can be caused by hyposecretion of insulin by the islets of Langerhans.
D) Correct.

[Answer to ques. #4]  PUD

[Answer to ques. #5]  C
Explanation: A) Melatonin helps regulate the release of gonadotropin and influences the body's clock.
B) Iodine can be used as a treatment of the thyroid.
C) Correct.
D) Cortisone is used as an anti-inflammatory agent.

[Answer to ques. #6]  LES

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